Writing instrument



FIG. 1 is a side view from the top of FIG. 5.

FIG. 2 is a side view from the bottom of FIG. 5.

FIG. 3 is a side view from the left of FIG. 5.

FIG. 4 is a side view from the right of FIG. 5.

FIG. 5 is a top view of the writing instrument.

FIG. 6 is a bottom view of the writing instrument; and,

FIG. 7 is a perspective view of the writing instrument. 

I claim the ornamental design for a writing instrument, as shown and described. 